Boiler stay-bolt



No. 770,651. PATENTED SEPT. 20, 1904. J. PETERS & J. COLEMAN.

BOILER STAY BOLT.

APPLICATION FILED JUNE 14, 1904.

N0 MODFLv I/VVEIVTORS 7i M ATTORNEYS WITNESSES" Patented September 20,1904.

FFICE.

PATENT JOSEPH PETERS AND JOHN COLEMAN, OF EL PASO, TEXAS.

BOILER STAY-BOLT.

SPECIFICATION forming part of Letters Patent No. 770,651, datedSeptember 20, 1904.

Application filed June 14, 1904.

To all whom it may concern:

Be it known that we, JOSEPH PETERS and JOHN COLEMAN, citizens of theUnited States,"

residing at El Paso, in the county of El Paso and State of Texas, haveinvented a new and useful Improvement in Boiler Stay-Bolts, of which thefollowing is a specification.

Our invention is in the nature of a novel form of steam-boiler stay-boltdesigned to connect the crown-sheet of the fire-box with the outsideshell of the boiler; and it consists in such construction ofstay-bolt'and the combination of the-same with the crown-sheet andboiler-shell as will secure a strong connection of these parts, whichwill compensate for expansion and contraction and be capable ofadjustment, and which will also facilitate the making of repairs and thetightening up of the stay-bolts against leakage, as will be hereinafterfully described with reference to the drawings, in which Figure 1 is avertical cross-section taken through the boiler-shell and furnacefire-box, showing the stay-bolts in place. Fig. 2 is an enlargedsectional view of one of the staybolts and its connection.

In the drawings, A represents the outer shell of the boiler, and A theinner shell, forming the crown-sheet of the fire-box.

B C are the two parts of the stay-bolt. The part B is a bolt of suitablelength having at its lower end a round flanged head I), provided with asquare terminal projection 6. Just above the flanged head 6 the shank ofthe bolt is screw-threaded, and this screwthread is embraced by ascrew-threaded sleeve 6 between which and the flanged head 6 thecrown-sheet A is clamped and held with a steam-tight joint. The functionof the sleeve is threefold. In the first place it forms one jaw of theclamp between which the crownsheet is held. In the second place ithouses and completely protects the threads of the bolt which are insidethe water-space from being rusted and encrusted with deposits, and thusmaintaining these threads bright and clean, so that when the sleeve isremoved the bolt B may be screwed out through the intermeshing threadsof the crown-sheet without mutilating the threads or weakening of theSerial No. 212.5I'7. (No model.)

bolt at this point. In the third place the sleeve 5 forms abackthrust-bearing for the calkingtool in tightening up leaks around thehead I). This calking-tool in being driven by the hammer-blows in thedirection of the arrow m, Fig. 2, finds the resistance of the sleeve Z2above the crown-sheet and allows the sharp edge of the flange b to bespread and tight ened against the crown-sheet, whereas if the sleevewere not there these blows of the calking-tool would bend upwardly theedges of the crown-sheet and increase the leakage. In this connection itwill be understood that it is necessary that the sleeve b must hug thebolt closely clear down to the crown-sheet, and thus completely fillsthe angle between the crown-sheet and the sides of the bolt.

At the upper end of the bolt there is formed a screw-thread, and this isprovided with a half-round nut B, which is received between the twobranches of a yoke C, which has an opening 0 at its lower end largeenough to allow the screw-threaded end of bolt B to pass freely throughit, but smaller than the halfround nut B, which rests in a seat in thelower end of the yoke and forms a sort of ball-andsocket joint. Theupper end of the yokeC is formed with a screw-threaded stem which isscrewed into a screw-thread of the boiler-shell and is upset on theoutside by riveting to form the external head 0.

The object of this two-part stay-bolt is to allow for expansion andcontraction between the crown-sheet and boiler-shell and also permits anadjustment of the stay-bolt to increase or diminish its length, ascircumstances may require. the upper screw-threaded end of the stay-boltwhen the latter is screwed directly into the boiler-shell, the yokebeing permanently fixed in the boiler-shell and the bolt portion B beingdetachable therefrom. It also avoids the necessity of having anabsolutely accurate alinement between the screw-threaded hole in theboiler-shell and that of the crown-sheet.

Having thus described our invention, what we claim as new, and desire tosecure by Letters Patent, is-

1. A two-part stay-bolt, one part being adapted to be rigidly connectedto one wall It also avoids the breaking ofi of IOO and the other part tothe other wall, and the two parts being connected together at anintermediate point with a loose take-up connection substantially asdescribed.

2. A two-part stay-bolt, one part being made as a yoke adapted to berigidly secured in one wall and the other part being made as a headedbolt adapted to be rigidly secured in the other wall, the yoke beingformed with a longitudinal opening and a round interior seat and thebolt being formed with a screwthreaded end which passes into thelongitudinal opening of the yoke and carrying a nut with a round bearingagainst the yoke-seat substantially as described.

3. The combination with a steam -boiler "crown-sheet; of a stay-bolthaving a'flanged angular space between the crown-sheet and the shank ofthe bolt for the purpose of resisting the strain of the calking-tool andfor housing and protecting the screw-threads substantially as described.

4. A two-part stay-bolt comprising a bolt portion having at one end aflanged headia screw-threaded shank and a screw-threaded sleeveencompassing the shank and also a screw-threaded upper end with ahalf-round nut, and a yoke portion having a longitudinal openingreceiving the half-round nut at one end and a screw-threaded stem at theother end adapted to be turned into and riveted in the boiler-shellsubstantially as described.

JOSEPH PETERS. JOHN COLEMAN.

Witnesses:

FRANK GANN, J. H. RUssELL.

